The general purpose of this research is to provide a description and explanation of transfer and interference phenomena in verbal learning and to apply these principles to the study of forgetting. The first part of the proposal emphasized an examination of the processes involved in the production of interference which is under the direct control of the investigator. Four general topics were discussed: the elicitation hypothesis, the unlearning of specific and contextual associations, the role of response competition, and a study of forgetting under conditions of massive amounts of interference from previously learned material. The second half of the proposal was devoted to an analysis of an interference theory of forgetting which is based upon extra-experimental sources of interference. A discussion of its present shortcomings was given, together with a program of research designed to determine the reasons for these difficulties. These suggestions consisted of attempts to increase the elicitation of the material to be recalled and refinements of experimental techniques and procedures used to study retention. Finally, experiments were proposed which involved the introduction of laboratory produced interference in the study of extra-experimental sources of interference.